Recurrences of Superficial Bladder Carcinoma are Associated with a Raise of CD8highCD57+ and CD8low T Lymphocytes in Peripheral Blood

Immunotherapy with BCG is effective in patients with recurrent superficial bladder carcinoma. This therapy involves Interleukin-2 (IL-2), but little is known about the immunological parameters involved in superficial bladder car- cinoma. We have monitored immunological parameters in twenty patients with superficial bladder carcinoma treated with transurethral resection (TUR) followed by IL-2 instillation. Cell numbers of peripheral blood leukocyte subpopulations were counted before surgery and during follow-up after surgery. During follow-up, we compared the cell counts in pa- tients with and without a recurrent tumour. We used the values of healthy matched controls as a reference. Recurrent dis- ease in patients corresponded with a significant increase in CD8 + lymphocytes, and especially the CD8 high CD57 + and CD8 low subpopulations. The phenotype of these T lymphocytes belongs to cells with an immunosuppressive function. We hypothesize that these peripheral immune suppressive cells facilitate tumour recurrences or that tumour recurrences cause an increase in peripheral immune suppressive lymphocytes.